US 2010/0304143 A1 · PRODUCTION OF Si02-COATED TITANIUM DIOXIDE PARTICLES WITH AN ADJUSTABLE COATING

Abstract

The present invention relates to a process for producing coated nanoparticles comprising a core comprising at least one first substance and at least one envelope at least partly surrounding the core and composed of at least one further substance, in a streaming system, to nanoparticles which can be produced according to this process, to nanoparticles comprising a nonporous core comprising at least one first substance and at least one porous envelope at least partly surrounding the core and composed of at least one further substance, the nanoparticles having a narrow particle size distribution, to the use of such nanoparticles in photocatalysis and to apparatus for carrying out the process.

Claims16

Dependent claims

-15. (canceled)

A process for producing coated nanoparticles comprising a core composed of at least one first substance and at least one envelope at least partly surrounding the core and composed of at least one second substance, in a streaming system, said process comprising the steps of:

(A) providing a main stream composed of a reaction gas or aerosol comprising at least one precursor compound of the at least one first substance present in the core of the coated nanoparticle,
(B) converting by thermal reaction in the main stream the at least one precursor compound present in the reaction gas or aerosol of step (A) into the corresponding at least one first substance to form the core of the nanoparticles to be produced,
(C) adding in a cross stream with regard to the main stream from step (B) a further reaction gas or aerosol comprising at least one precursor compound of the at least one second substance present in the at least one envelope,
(D) converting by thermal reaction in the main stream the at least one precursor compound present in the reaction gas or aerosol of step (C) into the corresponding at least one second substance to form the at least one envelope of the nanoparticles to be produced, and
(E) rapidly cooling the nanoparticles obtained in step (D), by adding a coolant to the main stream, wherein the rate of cooling in step (E) is at least 104 K*s−1.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application

12/675,432Filed 27 Aug 2008

Priority

EP 07115104.728 Aug 2007

Published

2 Dec 2010

Term ends

Not estimatedThe source records don’t support an estimate.

Classification28 codes

B01J 35/39
Characterised by their physical properties: photocatalytic properties
B01J 2/003
Processes or devices for granulating materials , e.g. fertilisers in general; Rendering particulate materials free flowing in general, e.g.…
B01J 2/04
By dividing the liquid material into drops, e.g. by spraying, and solidifying the drops: in a gaseous medium
B01J 19/24
Chemical, physical or physico-chemical processes in general; Their relevant apparatus: stationary reactors without moving elements inside

PRODUCTION OF Si02-COATED TITANIUM DIOXIDE PARTICLES WITH AN ADJUSTABLE COATING

Life of this patent

PRODUCTION OF Si02-COATED TITANIUM DIOXIDE PARTICLES WITH AN ADJUSTABLE COATING

Life of this patent

Abstract

Claims16